The 49-year-old actress attended Comic-Con in San Diego for her first time this week to promoted her new film, "Elysium" with Matt Damon. But Foster was overwhelmed by the excited fans and blames her "Panic Room" co-star Kristen Stewart (a Comic-Con pro after promoting "Twilight") for not preparing her.

In a 2011 interview with The Hollywood Reporter, Foster said she was surprised Stewart decided to continue acting after filming "Panic Room."

"I just love Kristen Stewart, but I didn't think she'd choose to be an actress," she explained of the now popular "Twilight" star. "I said to her mom, 'She doesn't want that, right?' And she's like, 'Well, yes, she kind of does.’ Because she's very much like me: She's not comfortable in life being a big externally, emotional person, beating her chest, crying every five minutes. I felt she was such an intelligent technician, so interested in camera -- I thought that would translate to other things."

But Stewart revealed at Comic-Con last week during the press conference for The "Twilight Saga: Breaking Dawn -- Part 2" that she wishes she could have used her acting skills even more in the film. The actress shared her disappointment with fans that her vampire sex scenes with costar Robert Pattinson (also her real-life boyfriend of over three years) were restricted.

"The ratings, man!" she said. "In the second one, we just wanted to be animals. We're not human anymore. How do you do that? We tried, and they told us it was rated R, and we were like [snaps fingers]. So, yeah, I'm going to stop."